As the value and use of information continues to increase, individuals and businesses seek additional ways to process and store information. One option available to users is information handling systems. An information handling system generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes thereby allowing users to take advantage of the value of the information. Because technology and information handling needs and requirements vary between different users or applications, information handling systems may also vary regarding what information is handled, how the information is handled, how much information is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated. The variations in information handling systems allow for information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, information handling systems may include a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more computer systems, data storage systems, and networking systems.
A number of different communication protocols are utilized by current information handling systems. These communication protocols include, for example, InfiniBand (EB), Fibre Channel (FC), PCI (Peripheral Component Interconnect) Express (PCIe), and Ethernet/IP (Internet Protocol) protocols. Traditional implementations for these protocols have provided confirmed delivery of data. However, for the Ethernet protocol, this confirmed delivery has been attempted at a relatively high communication layer thereby causing inefficiencies in utilizing the Ethernet protocol if confirmed delivery is desired or required.
FIG. 1 (prior art) is a block diagram for a layered comparison 100 for the OSI (Open Systems Interconnect) layer model applied to the IF, FC, PCIe, and Ethernet/IP protocols. A check mark identifies the layer responsible for guaranteed or confirmed packet delivery in each protocol. As shown in FIG. 1 (prior art), the OSI layer model has seven layers. Layer 1 is the PHYSICAL layer representing bits being communicated including bit format and conversion. Layer 2 is the DATA LINK layer representing packets of bits being communicated including physical addressing. Layer 3 is the NETWORK layer representing packets being communicated including routing and addressing. Layer 4 is the TRANSPORT layer representing communication transport segments and can be used to provide reliable communications. Layers 5-7 represent data layers including a SESSION layer where connection establishment occurs, a PRESENTATION layer where data representation and encryption occurs, and a APPLICATION layer representing the user endpoint.
Each of the protocols shown in FIG. 1 (prior art) implement the OSI Layers differently. For the IB protocol, Layer 1 is a physical layer. Layer 2 is a MAC (machine address code) and encode layer. Layer 3 is a network layer. Layer 4 is an IBA (InfiniBand Architecture) operations layer. And Layers 5-7 are implemented by applications. For the FC protocol, Layers 1-4 are implemented according to FC protocols FC-0, FC-1, FC-2, FC-3 and FC-4. Layers 5-7 are implemented by applications. For the PCIe protocol, Layer 1 is implemented with PCIe LLP (Lower Layer Protocol). Layer 2 is implemented with PCIe DLLP (Data Link Layer Protocol). Layers 3-5 are implemented using the PCIe TLP (Transaction Layer Protocol). Layer 4 is also implemented using the PCIe DLLP. Layer 6 implemented as a driver model layer. And Layer 7 is implemented as a PnP (Plug and Play) model. For the Ethernet/IP protocol, Layer 1 is the physical Ethernet. Layer 2 is implemented as STP (Spanning Tree Protocol) or VLAN (virtual local area network) layers. Layer 3 is implemented using IP packets. Layer 4 is implemented with TCP/UDP (Transmission Control Protocol/User Datagram Protocol). Layer 5 is represented by sockets. Layer 6 is ASCII communications. And Layer 7 can be an application such as TELNET.
For each of these protocols, prior solutions have provided confirmed delivery at particular layers of the OSI Layer Model. These layers are identified with check marks 102, 104, 106 and 108, respectively. Ethernet is a relatively unreliable protocol that depends upon the upper protocol layers, such as the Layer 4 protocol TCP (Transmission Control Protocol) represented by check mark 102, to provide guaranteed packet delivery. Thus, Ethernet is disadvantaged when compared to PCIe and FC, both of which provide guaranteed packet delivery at Layer 2 as represented by check marks 104 and 106, respectively. IB also provides improved guaranteed delivery at a hardware-embedded Layer 3 (labeled Network) as represented by check mark 108.
This capability for lower level guaranteed delivery is important in systems where guaranteed delivery is desired without the overhead of the upper layers. One example would be a chassis-based computer system using Ethernet or IP-based communications as a central fabric interconnect to provide access to a limited number of physical hardware communications devices by a larger set of blade servers. Guaranteed packet delivery typically requires that packets be tagged with sequence numbers so that an indication of out-of-order packets and dropped packets may be provided. Current methods of confirmed Ethernet packet delivery, however, are not efficient and can interfere with legacy systems.